FIELD OF THE INVENTIONThe present invention relates in general to digital communication system, and more particularly, to methods for delivering and receiving interactive multimedia content in the digital communication system.
BACKGROUND OF THE INVENTIONDigital broadcast communication systems such as DVB-H (Digital Video Broadcasting—Handheld), DVB-T (Digital Video Broadcasting—Terrestrial) or other client-server communication system, enable end users to receive digital content including video, audio, and data. Using a fixed or mobile terminal, a user may receive digital contents over a cable or wireless digital communication network. For example, a user may receive data such as a broadcast program in a data stream. Additional data associated with the broadcast program such as interactive multimedia contents including program title, news, interactive services, or additional audio, video and graphics, may also be available. The interactive multimedia contents can be previously stored at the server or generated during the broadcasting or multicasting of the program.
Interactive multimedia content is a service that aggregates interactive services with a conventional A/V broadcasting service. MPEG-4 Part20 designates interactive multimedia using the terms ‘rich media’. OpenTV and DVB designate interactive multimedia using the terms ‘interactive television’. The core idea of interactive multimedia is adding one or more interactive multimedia to an original A/V stream. The content of the interactive multimedia, usually synchronized with the original A/V stream, will enable reaction to different user inputs. The processing of user inputs can be either handled locally or remotely, in the latter case using a bi-directional channel.
The content of the interactive multimedia service is a collection of multimedia data, such as graphics, text, audio and video etc, which may change over time based on the A/V stream. The A/V stream has its own timeline, here, the timeline is a term used to describe that a video/audio sequence is ordered by time stamp. The corresponding contents of interactive multimedia content also have a timeline, which relates to this A/V stream timeline by a reference, such as a start point tag. That is, there is a temporal synchronization between the corresponding interactive multimedia content and the A/V stream. The start point tag refers the specific time point of the timeline of A/V stream. When the A/V stream plays to the specific time point, an event is triggered to play the corresponding interactive multimedia contents.
The interactive multimedia contents are shown according to users input during a specific period of timeline of A/V stream. For example, a sports TV (television) channel may be associated with a pop-up interactive multimedia content that describes an athlete who just scored a goal and the video scene of the athlete is being broadcasted. When the video scene of the program changes, the other interactive multimedia contents will be used accordingly. The transmitted interactive multimedia content can be either integrally multiplexed into conventional A/V stream or sent in a separate channel.
According to the above, interactive multimedia services can be an interactive experience during a specific period of the A/V stream between a multimedia server such as a service providing device and the end users. During the specific period users may send requests for a type of interactive multimedia to the service providing device, and then the service providing device will send the requested multimedia content to the users. However, the bandwidth resource used by interactive multimedia services for multimedia requesting and multimedia delivery during the specific period will not scale well with growing numbers of users. This may be the case for a multicasting communication environment or a broadcasting TV network with return channel.
Therefore, an improved method for requesting and delivering interactive multimedia content is needed.
SUMMARY OF THE INVENTIONThe invention concerns a method used in a service providing device for delivering interactive multimedia content to a plurality of client devices during a specific period when a corresponding audio and/or video stream associated with the interactive multimedia content is being delivered, comprising: receiving a request for a given multimedia content, from at least one of the plurality of client devices; disabling the plurality of client devices from sending further requests for said given multimedia content to the service providing device, according to a predetermined condition; and delivering the multimedia content to the plurality of client devices in response to said condition.
The invention also concerns a service providing device for implementing the above mentioned method for delivering an interactive multimedia content in the multimedia communication network. The service providing device comprises a transmission processing device for receiving a request for the interactive multimedia content from at least one of the plurality of client devices; disabling the plurality of client devices from sending the request to the service providing device, according to a predetermined condition; and delivering the interactive multimedia content to the plurality of client devices, by a processor and a communication interface.
The invention also concerns a method for receiving a interactive multimedia content, used in a client device of a communication network, comprising: receiving a request for a given multimedia content to be sent to a service providing device of the communication network, from an input device of the client device; disabling sending a request message corresponding to the user request to the service providing device according to a predetermined condition; and displaying the interactive multimedia content received from the service providing device.
The invention also concerns a client device for implementing the above mentioned method for receiving interactive multimedia content in the multimedia communication network. The client device comprises a processor for receiving a request for the interactive multimedia content to be sent to a service providing device of the communication network through a user interface, disabling sending the request to the service providing device according to a predetermined condition; and displaying the interactive multimedia content received from the service providing device through a communication interface.
BRIEF DESCRIPTION OF DRAWINGSThese and other aspects, features and advantages of the present invention will become apparent from the following description of an embodiment in connection with the accompanying drawings:
FIG. 1 is a schematic block diagram showing a digital communication system used to explain an embodiment of the invention;
FIG. 2 is a flow chart showing a method for delivering interactive multimedia contents according to the embodiment of the invention;
FIG. 3 is an illustrative table showing an interactive multimedia list according to the embodiment of the invention;
FIG. 4 is a flow chart showing a method for receiving interactive multimedia contents according to the embodiment of the invention;
FIG. 5 is a block diagram showing a transmission processing device according to the embodiment of the invention; and
FIG. 6 is a block diagram showing a client device according to the embodiment of the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTSFIG. 1 is a schematic block diagram showing adigital communication system100 in which the method of the present embodiment of the invention is implemented. As shown inFIG. 1, a plurality of client devices108-1 to108-n, such as personal digital assistants (PDA), mobile terminals or television receivers, are in communication with aservice providing device110 including service sources through acommunication network105. In a variant of the embodiment, the service sources are physically separate from theservice providing device110, and connected with it through thecommunication system100. The service source may include several service providers, such asvideo program source102 and other interactivemultimedia content source104 as shown inFIG. 1, so that theservice providing device110 can provide program content, interactive multimedia information and description of their service to theclient devices108 in a channel after the processing of thetransmission processing device106. According to the embodiment, thetransmission processing device106 includes a disablingdevice107 for disabling the client devices108-1 to108-nfrom sending interactive multimedia requests to theservice providing device110 according to a predetermined condition.
Theclient devices108 can be assigned to several multi-cast groups, and receive digital information multi-cast or broadcast from theservice providing device110. For example, clients108-1 and108-2 are assigned to a multicast group, and clients108-3 to108-nare assigned to another multicast group.
During a specific period when a video scene of a program is being broadcasted, an corresponding interactive multimedia information list including multiple options of interactive multimedia contents, is transmitted to theclient devices108 along with the currently broadcast program in the channel, and then the specific interactive multimedia information is delivered to the corresponding client devices based on specific requests from the users. The interactive multimedia information list can be a text table, graphics menu or the like, and can change e.g. when the scene of the video program changes.
FIG. 2 is a flow chart showing a method for delivering interactive multimedia content according to the embodiment of the invention. Suppose that some users are enjoying a football match broadcast with interactive multimedia service, and a player has just scored a goal. At this specific time period, an option list of the corresponding interactive multimedia contents including the following options: background of the athlete, history of the team, and score of this team at this match and so on, are shown on a display of the client devices.
If one user using client device108-1 wants to see the background information of the football player in the list, he/she sends a request for a given interactive multimedia content, that is, a request for the background information of the football player to theservice providing device110 by an input device such as a remote control device, and theservice providing device110 receives the request from the client device at step S201. According to the embodiment, theservice providing device110 maintains a table showing the requested interactive multimedia as shown inFIG. 3. This table includes three columns: interactive multimedia type, request count and threshold value. The column of interactive multimedia type means interactive multimedia options relating to the current program, such as background of athlete A T401, history for the current team T402, score of the team T403 and so on. The request count means respective request number received from users. The threshold value is the predetermined condition for disabling the request sending, such as request number for respective interactive multimedia, and if the request count reaches the threshold value, theservice providing device110 will inform allclient devices108 to disable sending a request for this interactive multimedia content, and in response to the predetermined condition, start to delivery, such as broadcast or multicast, the requested interactive multimedia content to theclient devices108.
Returning now toFIG. 2, after receiving a request for a given interactive multimedia from a client device, theservice providing device110 can obtain the type of the requested interactive multimedia at step S202, and at step S203 accumulate the number of times this type of interactive multimedia has been requested in the table as shown inFIG. 3. Here, if the requested type is a new type in the table, this new type will be added to the table and the related request count is set to 1. If the request type already exists in the table, it will be incremented by 1. According to the embodiment, the tables for each request type are not maintained in a memory of server, but are recorded in a database. The table can be refreshed regularly as a function of the predetermined condition and the received request.
Then at step S204, theservice providing device110 determines whether a request count has reached the pre-determined threshold. If no, it will continue the accumulation at step S203. If yes for a specific type of interactive multimedia request, theservice providing device110 will broadcast or multicast a disable command message to allclient devices108 to disable the corresponding request at step S205. The disable command message indicates that theservice providing device110 has received the required number of these requests and is preparing to process the requests. For example, if other users also want to see the same interactive multimedia, these users still use the input device of theirclient devices108 to make such a request, but these requests will not be sent to theservice providing devices110 through the uplink channel of thecommunication network105. The specific process of the client device will be described in detail later.
After disabling a type of interactive multimedia request, theservice providing device110 will deliver the corresponding requested interactive multimedia contents to theclient devices108 in response to the predetermined condition at step S206. Thus, allclient devices108 can receive the delivered interactive multimedia contents (even those having not sent their request before a disablement message), and those having sent the type of interactive multimedia request by an input device can display the requested interactive multimedia to the users. Then the request count in the table will be reset at step S207 if the football match is still playing, and this type of interactive multimedia can be requested again. At the same time, theservice providing device110 sends a command to all clients to enable relative request operations when the interactive multimedia information list and the corresponding scene of current program is still alive, and if the scene has changed, a updated list will be displayed to the users.
In another embodiment, theservice providing device110 may broadcast a disable command message to allclient devices108 to disable the corresponding request according to a predetermined condition of a time period from receiving the first request of the respective multimedia type. Thus, the users that have requested the interactive multimedia contents can obtain the requested interactive multimedia contents after the time period, despite the insufficient number of requests. In addition, request count and time period threshold value can be combined to realize different embodiments, and the predetermined condition can be selected by one skilled in the art.
FIG. 4 is a flow chart showing a method for receiving interactive multimedia contents according to the above mentioned embodiment. When a user is watching a football match program broadcasted from aservice providing device110 by a client device108-1, a interactive multimedia information list of the current program, such as the above mentioned options including background of the athlete, history of the team and so on, is received at step S401, and is displayed on a display device of the client device108-1 at step S402. If the user wants to obtain content in the list, he/she can input a request command for the specific interactive multimedia content to be sent to theservice providing device110 by an input device of the client device108-1, that is, the client device108-1 receives an interactive multimedia request from input device at step S403. Here, the input device can be a part of the client device or can be a separate device.
At the same time, some users of other client devices108-2 to108-nmay also want to see this specific interactive multimedia content, and send a request to theservice providing device110. According to the above explanation ofFIG. 2, if the request count of this type of interactive multimedia reached the predetermined threshold value, theservice providing device110 will broadcast a disable command message to theclient devices108.
After receiving a type of interactive multimedia request from the input device, the client device108-1 will determine whether this type of interactive multimedia is enabled or not at step S404, if the answer is yes, the client device108-1 can send the request to theservice providing device110 at step S405 via a uplink channel of thecommunication network105, and if the answer is no, the client device108-1 will not send the request. Then the client device108-1 will receive the requested interactive multimedia broadcasted by theservice providing device110 and display it to the user at step S406.
On the other hand, if a user doesn't input a given type of interactive multimedia content, but receives that type of interactive multimedia content broadcasted from theservice providing device110 by theclient device108, then it will not display this interactive multimedia content to this user.
In another embodiment, theclient device108 may disable the sending of interactive multimedia requests to theservice providing device110 voluntarily according to a predetermined condition, and the predetermined condition includes a time period from receiving interactive multimedia information list of the broadcasting program. For example, if the time period is reached, even if the user initiates sending a request using the input device, theclient device108 will not forward the request to theservice providing device110. In addition, the predetermined condition is that whether a disabling command is received from theservice providing device110. When the requested multimedia content is received by theclient device108, it will be displayed to the user.
FIG. 5 is a block diagram showing thetransmission processing device106 of theservice providing device110 according to the embodiment of the invention. Thetransmission processing device106 is adapted to process the digital information fromvideo program source102 and other interactivemultimedia content source104, and handle communication with theclient devices108 throughcommunication network105 such as a digital broadcast network. The digital information process may comprise encapsulation, modulation and transmission. The interactive multimedia content can be either integrally multiplexed with a conventional A/V stream or separately transmitted. While on theclient device108, an interactive multimedia engine previously installed on it is responsible for rendering the media transparently over A/V stream.
Thetransmission processing device106 comprises acommunication interface502 for receiving data from the service source, and exchanging data with a plurality ofclient devices108 through thecommunication network105, aprocessor504 coupled with thecommunication interface502 for processing data and for controlling thecommunication interface502, so as to exchange data and provide service to theclient devices108 based on the above embodiments, and a disablingdevice505 for providing a disable command message to theclient device108 through thecommunication interface502, according to the multimedia request table processed by theprocessor504. According to another embodiment, the disablingdevice505 can be a part of theprocessor504.
Thetransmission processing device106 also includes amemory506 for storing the buffered video program, the other interactive multimedia contents, and executable instructions and data for programming theprocessor504 according to the present embodiment. Preferably, thecommunication interface502, theprocessor504, the disablingdevice505 and thememory506 can be combined in whole or in part and fabricated as an integrated circuit.
As mentioned above,transmission processing device106 of theservice providing device110 broadcasts or multicasts video program along with a corresponding interactive multimedia list toclient devices108 via thecommunication interface502. Then, thetransmission processing device106 receives interactive multimedia requests, accumulates the request counts according to the procedure flow shown inFIG. 2, and then broadcasts or multicasts a disable command from the disablingdevice505 and interactive multimedia contents stored in thememory506.
FIG. 6 is a block diagram showing theclient device108 according to the embodiment. Theclient device108 comprises aprocessor606 for controlling acommunication interface604 coupled to theprocessor606 to communicate with thetransmission processing device106, auser interface602 comprising well-known elements, such as a keypad, a display, and audio transducers etc. and a disablingdevice607 for disabling sending a multimedia request to theservice providing device110 through thecommunication interface604, according to a disabling instruction from theprocessor606. The disabling instruction is obtained from a predetermined condition including a disabling command received from theservice providing device110, and a predetermined time interval from receiving the interactive multimedia content list. According to another embodiment, the disablingdevice607 can be a part of theprocessor606.
In addition, theclient device108 includes amemory608 coupled to theprocessor606, and storing video program, interactive multimedia contents, and executable instructions and data for programming theprocessor606 in accordance with the embodiment. Preferably, theprocessor606, thecommunication interface604, the disablingdevice607 and thememory608 can be combined in whole or in part and fabricated as an integrated circuit.
As mentioned above,processor606 ofclient device108 controls thecommunication interface604 so as to communicate with thetransmission processing device106 and receive program and other interactive multimedia information according to the input of users byuser interface602.
The foregoing merely illustrates the embodiment of the invention and it will thus be appreciated that those skilled in the art will be able to devise numerous alternative arrangements which, although not explicitly described herein, embody the principles of the invention and are within its spirit and scope.